I wanted to post a follow up to update the problem I'd had with this amp. Shawn inspected the board and found a couple of stressed resistors, and several more suspect resistors. After conferring with Jeff, it was determined to update all of the board level resistors with Mills and PRP types. Also updated was the DIY silver internal IC wire I'd previously used, replacing with Neotech NEI-3001.

I've had the board back, installed, biased, and breaking in now for about 2 weeks. The "crackle" in the left channel is gone. I've now got about 15 hours on it. Immediately a new level of transparency and dimensionality was apparent. A little initial brightness is mellowing and the amp is simply more of everything. Much more shimmer and decay in the highs, exceedingly natural mid band, and as punchy as any tube amplifier has a right to be. I'm WAY pleased.

My thanks to Shawn and Jeff for the world class parts and service... reasonable rates too.